The Metropolitan New York Registry of Breast Cancer Families is one of six international sites comprising the Cooperative Family Registry for Breast Cancer Studies (CFRBCS). The goal of the CFRBCS has been the development of a comprehensive resource for interdisciplinary genetic epidemiology studies addressing breast cancer risk and prognostic factors. The NY Registry has recruited 1102 families and collected biospecimens, pedigree and epidemiologic data on family members. In this competing continuation, the goals are to: recruit additional families of African American, Hispanic and Asian Heritage; increase the number of relatives participating per family complete collection of biospecimens, including tumor tissue blocks, and data from consented participants; conduct comprehensive follow-up 5 years after enrollment including data on current cancer status of all relatives in the family pedigree; continue biannual mailings of newsletters and invitations to educational, community-based seminars; maintain the integrity of the database, create new databases as needed, update data files and submit data to the CFRBCS Informatics Support Center; maintain biospecimens repository; process and bank additional biospecimens from newly recruited families complete retrieval of pathology materials. These goals are necessary for the NY Registry to provide the resources needed for ongoing CFRBCS research, collaborative studies with external scientists, and for the extensive multi-disciplinary research modules. Included in this renewal application. Members of the NY Registry team will take a leadership role in three of the research modules: Module 2-DNA repair genes and breast cancer, Module 9-Genetic modifiers of BRCA penetrance in Ashkenazim and Module 10-Module-Estrogen-gene variants and breast cancer. The NY Registry will also contribute resources and expertise to the other research modules proposed by CFRBCS colleagues: Module 1- Systematic follow-up study, Module 3-BRCA + mutations in minority families, Module 4-Environmental modifiers of breast cancer risk in carriers of BRCA mutations, Module 5-Prognosis and pathologic characteristics of heritable breast cancer, Module 6-Cancer screening and prevention in BRCA1 and BRCA2 mutation carriers, Module 7- Participation in a family based cancer registry. behavioral and social outcomes, Module 8-Outcomes of genetic testing among Ashkenazim families, Module 11-identification of novel genes involved in breast cancer susceptibility, Module 12-Mammographic densities and familial breast cancer, and Module 13-Penetrance and prevalence of BRCA1/2 mutations in the CFRBCS. Renewal of the CFRBCS will enable our collaborators team to expanded and enhanced our unique resources for multi-disciplinary research with the potential for identifying new avenues for prevention, detection and treatment of breast cancer.